1. Field of the Invention
The present invention generally relates to power distribution connector apparatus for circuit boards, and more particularly relates to a current distribution rod connector apparatus for back-to-back sandwiched circuit boards.
2. Description of Related Art
The use of circuit boards in computer systems is well known. Typically, these circuit boards are printed circuit boards; that include an interconnected array of integrated circuits such as microprocessor chips, software programming chips and imprinted electrical circuits, all designed to provide the user with an efficient personal computer ("PC").
Initially, PCs were stand-alone devices, each containing separate hardware, operating system, application software and user data. However, as use of PCs spread within business organizations, the need for shared data and hardware resources grew, and local area network ("LANs") came into being. ALAN (or its more-geographically-dispersed .counterpart, the wide area network ("WAN")) comprises a number of PCs ("clients") linked to one another (typically by a high speed serial communications link) and centers around a relatively high performance PC (a "server") that delivers application programs and data to the clients and manages system-wide resources, such as secondary storage units and printers.
Because the server is designed to serve several PCs in a given LAN, the storage capacity, as well as the processing capability of these LAN servers is very large. Consequently, their processing and storage capacity has grown over the years with the increasing demand placed on them by larger networks designed to manipulate more data. Many of these network systems employ large computer systems housed in rack-type cabinets that are designed to house a plurality of interconnected circuit boards and other electronic components.
In the past, these circuit boards have been powered by conventional power strips or busbars. While such devices are adequate for applications in personal computers, they are presently less desirable in larger rack-type cabinet computers that house a plurality of circuit boards. The reason for this is that conventional power strips and busbars are not able to supply sufficient current to a plurality of circuit boards that are comprised of today's faster, current-hungry microprocessor chips. As the need for management of large amounts of data has increased, microprocessor chips have been redesigned to operate at extraordinary fast megahertz speeds. Unfortunately, however, increasing the speed of the microprocessor chips has also increased the amount of current needed to operate the chips. As a result, there is presently a need for a high density current system capable of delivering the amount of current necessary to operate today's faster microprocessor chips.
In a conventional power strip or busbar, the current has to be "summed" and then redistributed. That is, most busbars or power strips are supplied by a ribbon cable having either a multi-pin male or multi-pin receiving female connectors. Each pin or pin receiving opening in the connector receives a portion of the total current from the small wire supplying the current to that particular pin or pin receiving opening. The total current received by the connector is then re-distributed to the various components attached to the board. The small wire supplying the connector and the corresponding small wire imprinted in the busbar, which leads from the connector to the various distribution points, are designed to carry only so much current. Thus, with today's faster current-hungry microprocessor chips, it is more difficult to supply the amount of current that is needed to operate these chips using conventional busbars or power strips. One solution, of course, would be to increase the number of busbars in the system. However, increasing the number of power strips or busbars is not an acceptable solution because they require more space in an already cramped hardware environment and add to the overall cost of the system.
Furthermore, although conventional busbars or power strips could be modified to transmit more current, there are disadvantages associated with making such modifications. First, any such modification may require the use of expensive highly conductive alloys such as gold or platinum, which significantly increase the overall cost of the unit. Second, even with these modifications, the base structures of the busbars and power strips would still require a significant amount of housing space.
In an attempt to solve this current problem, the prior art provides high density current power pins that are employed to supply current to various electronic apparatus. However, the use of these devices have been typically limited to three applications. First, the pins are combined with connectors to supply current to a single unit, whether that be a circuit board with microprocessors or to some other type of electrical component. Second, they are either used to supply current to individual units from a busbar from which several electrical connectors and pins extend or used to supply current to two daughter boards from a separately powered mother board. Third, they are used to transfer digitized signals from one circuit board to another.
While these designs and applications address some of the problems previously mentioned, they are lacking in many respects. For example, the first application mentioned above is not well suited in a rack cabinet application where a plurality of circuit boards are arranged in a parallel series. In such applications, each board would have its own pin and power source connected to it. Therefore, several power pins and connectors would have to be utilized to supply current to the plurality of boards typically found in a rack cabinet. Furthermore, the numerous connectors and pins would require more space and can thus limit the way in which the circuit boards may be arranged within the rack cabinet. Additionally, the plurality of connectors and pins in such an application would add to the overall cost of the server unit. Likewise, the second application is not well suited for use in a rack cabinet because a busbar or power strip, which may have several electrical leads extending to several pins and connectors, would be employed. As previously discussed, the busbar or power strip is inadequate in with respect to its current distribution capabilities. In either the first or second applications, however, the cost of the server unit increases due to the additional electrical hardware that is needed, and the problems associated with housing this additional hardware are still present.
The third application is, of course, not directed to the transmission of current sufficient to run a current-hungry microprocessor, but is instead directed to the transmission of smaller amounts of current for sending and receiving digital signals between circuit boards.
Therefore, it can readily be seen that there is a need in the art for a current distribution system that is inexpensive, compact and one that is capable of supplying adequate current to a plurality of parallel circuit boards. Accordingly, it is an object of the present invention to provide a current distribution rod and system that is capable of supplying an adequate amount of current to a plurality of circuit boards arranged in a parallel series.